Method of preparing adducts



Patented May 27, 1952 assasss 7 METHOD OF PREPARING ADDUCTS Joachim Dazzi, Dayton, Ohio, assignor to Monsanto Chemical Company, St. Louis, Mo., a corporation of Delaware No Drawing. Application April 11, 1950 Serial No. 155,341

13 Claims.

'This invention relates to improvements in the preparation of adducts formed by theaddition reaction of maleic anhydride with olefinic, nonconjugated fatty acids of from to 24 carbon atoms and esters of said acids. It has particular reference to improving the color and clarity of such adducts.

The preparation of adducts by reaction of maleic anhydride with unsaturated fatty acids is well-known. (See U. S. Patent No. 2,188,882, to Clocker and the article by Ross, Gebhart, and Gerecht, which appears in the Journal of the American Chemical Society, p. 1373 (1946).) While the structure of such adducts has not been definitely-determined, it is believed that addition of the fatty acid or ester thereof, occurs at the double bond of the dicarboxylic acid. For example, the maleic anhydride-oleic acid adduct probably has the structure:

Owing to the uncertainty of the position of the fatty acid carbon at which attachment of the dicarboxylic residue occurs, as well as for the sake of brevity, the term adducts employed hereinafter will refer to the equimolar addition products of maleic anhydride and a fatty acid compound having the general formula YCOOZ wherein Y is an olefinic, aliphatic hydrocarbon residue of from 9 to 23 carbon atoms and Z is hydrogen or an alkyl group of from 1 to 8 carbon atoms.

Such adducts are compounds of great potential use in the chemical and related industries. Actual utilization of the adducts, however, has been somewhat limited by their poor color. For example, when following the procedure employed in the prior art there are generally obtained,

decolorization of the product in the addition reaction of maleic anhydride and monoolefinic, unsubstituted fatty acids.

These and other objects of the invention may be accomplished by the process of the invention in which the condensation of maleic anhydride and an olefinic non-conjugated fatty acid is conducted in the presence of a phosphorus compound having the general formula: v

in which R is a member of the group consisting of alkyl, phenyl, alkylphenyl, xenyl, and naphthyl radicals of from 2 to 12 carbon atoms and their mono-chloro substitution products, R is a' member of the group consisting of hydrogen and R, and X is a member of the group consistingof R, OR and OH.

One group of compounds having theabove general formula comprises phosphonic acids and their esters having the general formula:

0 n-i oa' R in which R is as defined above and R is a member of the group consisting of hydrogen and R. As examples of phosphonic acids and phosphonates having this structure may be meneven when using very pure grades of reactants,

opaque reaction materials of adark color that makes them unsuitable for many uses for which they could be otherwise employed.

Accordingly an object of the present invention is to provide a method for improving the color of such. adducts.

tioned n-butanephosphonic acid, n-hexanephosphonic acid, diethyl dodecanephosphonate, diphenyl n-octanephosphonate, (isopropyl) (ethyl) decanephosphonate, di-n-amyl benzenephosphonate, c-naphthalenephosphonic acid, bi-phenylphosphonic acid, diethyl chlorobenzenephosphonate, di-p tolyl benzenephosphonate, bis(p-ch1orophenyl) n-hexanephosphonate, thylbenzene phosphonic acid, etc. Another group of compounds encompassed by A the present invention consists of phosphinic acids and their esters having the general formula in which R is as defined above and R is a member of the group consisting of hydrogen andR. As illustrative of phosphinic acids and phosphinates us ful for decreasing olor formati e oi V reactants or th 'was bubbled through the n (ifthe half houf heating period. After 1 was diliited with-ether;washedseveraltimeswitli water-and; the wash water" was a'iialyaed maleic anhydride-fatty acid adducts may be mentioned dibutylphosphinic acid, bis(2-ethylhexyDphosphinic acid, the ethyl ester of di -noctylphosphinic acid, the chloroethyl ester of dibutylphosphinic acid, di-dodecylphosphinic acid,

contribute to the ducts. Inasmuch as v 1y takes place in the absence of the phOsphor-us compounds, the action of the added'fmaterial can not be considered to be catalytic. Only very small quantities of the phosphorus" compound:

5 compounds 7 darkening of desir ad;

the addition reaction readineed to be employed, say, from 0.5 per cent-by} weight to 5.0per cent by. weight of the maleic anhydride employed. Less than 0.3 "per cent generally has substantially no decolorizing effect andwhi-lequantities excess of'5-.0 per" cent may be employed, for purposer' r economy: itii's preferred-to limit the rarige'cf the" additive to notmore: than 5 per cent; thiSquantity being sufficientto give adducts' of great y improved C6101; V

1 The invention is further illustratedibut'not limited, by-thefollewifig"example: i

' EXAMPLE In this example there issummarized a series of experiments whichwere made according to the following general procedure: A p

. Intoaithree-necked fla'sk fit ed with an ag i-' tater. thermometer; condenser and an "inlet t'ube i there were placed the" unsaturated fatty acid, the maleie anhydride and 'thefphosphorus compound. The molar ratio of maleic" anhydri'defioleig-aci d used varied between 1:1 and 1.25:1. Thedfl-g'as'es or traces-ofmaleic anhydridefwerecolleete' over very' diluted;- aquebus sodium" hydroxide and a few drops of phenolplithalein". j The whole mixture was heated during a minute period from room temperature up to 200 C.

An inert gas, i. e., nitrogen, liquid during the first (liquid temperature) a rte s h tsurh'e'atiiigperiod at the temperatures indicated in the'table belo'w, t e mature-was 'rrie reaetitsfi'mixture was subsequently treated,

maleic anhydride. Low boiling materials removed: by heating the residue for 1 to zlheu s 232E C; batl-itemperature: at a'gpressure of L mm. Th'yields'varied betweerrfid to QB' percent and were based on-tlie-determination of un- Y reactedmaleic anhydride found in the filtrate and in'the solid residue minus the equivalent used to nea the" char-gets phosphorus compound. is ethodiwas" also checked by polarogfaphid w anhydi ide fouiid the "tree amersol-zas technical. ,-(Emery I ndustrieskrepresents distilied olelc acid,

{Based on charged maleic anhydride. 7

. 3After reaction mixture had been brought to 200 C.

Gardner Scale (Gardner color standards for varnishes, oils and lacquers).

6 Bis-(p-chlorophenyl)phosphinie acid.

7 D ethylbenzene phcsphonate. Dxphenyl 2-ethyl-hexane-phosphonate.

Quantities of" reactants indicated above are parts by weight.-

A-ll'of the above experiments were carried out in large test tubes fitted with cork stoppers wrapped in'metal foil. All were'heated simultaneously in the same oil bath.

ts shown-iiithe above table; iii the blank ex eriment 1, the'color er the aduuct's (iii-'tfi Gardner scale was" 16.3; The 'eifi eitey'or t trodiic'ed'phosphorusfcoinpoiiri decreased color valu of the add l thepre'sence of" the' pho'splio'riate each unit in the upper range of the Gardiifscal 1. 1n color vames otrmnt 7 te -1 e-retsfeSeat a dec dedly significant color ehane obtained the present process are Since iormatioir ofthe' presefitaddu add t on of quemole df 'tne'maieic-aiiiiydnaemtfi one mele of-the fatt'y acid cc iziip'fiiiid, the actalits" should be; present in subst tiellly cnlqmetrie proportions. qt y or eit" reactant actually preseht in the in al mi in unimportant, iri thatany "eiress' mate a'i recoverable froni the fiiialreaetioii m m reaction is efiected at temperataresvmitu ebe low the decomposition pointsof either the reactants or the product and preferably between temperatures of, say, between C. to 300 0.

Although the above ekample shows only the use of o1e1c acid as the fatty'aeidmomponem, other monoolefinic, unsubstitutediatty acids e. g.-,=10-. undecylemc acid, maybe similarlyreacted with male c-anhydride in the presence of the present phosphorus compouridsto give adductofgood color; Alsoinstead of using the free ftttit acids, there, may be-eniployedesters ofthe' same with all-pram. unsubstituted. alcohols; of from 1; to. s carbon ,atqms, ;e. g methyl ethyl, isopropyl n hexyl-or' Z-ethylheir'yl undecyl'atef or oleat the adductsthus obtained beingi clearer and lighter m color than adducts prepareaty prior methods. (111181 prefer toadd the phosphorus compound to the mixture of, maleic anhydride and the fatty ac d component before initiating the -reaction good results are obtained when the presentphosphorus compounds areqadded-at-an-intermediate' stage of: the' react ioii. For example, .thereaction mixture maybe heatedfor ai timeof} emanate tWo-hoursin the absenceiof thephes-pheruscom pound, and the reactionzinterrupted for-addition of the latter. However,:colorimmovemeht' is*not'- so 'proneunced. V

' Whilethe'addition vantageous. The addition reaction may also be efiected in the presence of an inert high boiling diluent, the use of a diluent being recommended when working with the higher esters, e. g., noctyl oleate.

What I claim is:

1. The process of preparing adducts which comprises heating at temperatures of from 150 C. to 300 C. a mixture comprising maleic anhydride, a fatty acid compound having the general formula YCOOZ wherein Y is a non-conjugated olefinic, aliphatic hydrocarbon residue of from 9 to 23 carbon atoms and Z is a member of the group consisting of hydrogen and alkyl radicals of from 1 to 8 carbon atoms, and a phosphorus compound having the general formula:

in which R is a member of the group consisting of alkyl, phenyl, alkylphenyl, xenyl and naphthyl radicals of from 2 to 12 carbon atoms and their mono-chloro substitution products, R is a member of the group consisting of hydrogen and R, and X is a member of the group consisting of R, OR and OH, the quantity of said phosphorus compound being from 0.5 percent to 5.0 percent by weight of the weight of the maleic anhlydride.

2. The process of claim 1 further defined in that the fatty acid compound is oleic acid.

3. The process of claim 1 further defined in that the fatty acid compound is undecylenic acid.

4. The process of preparing adducts which A comprises heating at temperature of from 150 1 in which R is a member of the group consisting of alkyl, phenyl, alkylphenyl, xenyl and naphthyl v radicals of from 2 to 12 carbon atoms and their mono-chloro substitution products and R is a member of the group consisting of hydrogen and R, the quantity of said phosphorus compound being from 0.5 per cent to 5.0 per cent by weight of the weight of the'maleic anhydride.

5. The process of claim 4 further defined in that the fatty acid compound is oleic acid.

6. The process of claim 4 further defined in that the fatty acid compound is undecylenic acid.

'7. The process of preparing adducts which comprises heating at temperatures of from C. to 300 C. a mixture comprising maleic anhydride, a fatty acid compound having the general formula YCOOZ wherein Y is a non-conjugated olefinic, aliphatic hydrocarbon residue of from 9 to 23 carbon atoms and Z is a member of the group consisting of hydrogen and alkyl radicals of from 1 to 8 carbon atoms, and a phosphorus compound having the general formula in which R is a member of the group consisting of alkyl, phenyl, alkylphenyl, xenyl and naphthyl radicals of from 2 to 12 carbon atoms and their mono-chloro substitution products, and R is a member of the group consisting of hydrogen and R, the quantity of said phosphorus compound being from 0.5 per cent to 5.0 per cent by weight of the, weight of the maleic anhydride.

8. The process of claim 7 further defined in that the fatty acid compound is oleic acid.

9. The process of claim '7 further defined in that the fatty acid compound is undecylenic acid.

10. The process of preparing adducts which comprises heating at temperatures of from 150 C. to 300 C. a mixture comprising maleic anhydride, oleic acid and n-octanephosphonic acid, the quantity of said phosphonic acid being from 0.5 percent to 5.0 percent by weight of the weight of maleic anhydride.

11. The process of preparing adducts which comprises heating at temperatures of from 150' C. to 300 C. a mixture comprising maleic anhydride, oleic acid and bis(p-chloropheny1)phosphinic acid, the quantity of said phosphinic acid being from 0.5 per cent to 5.0 percent by weight of the weight of the maleic anhydride.

12. The process of preparing adducts which comprises heating at temperatures of from 150 C. to 300 C. a mixture comprising maleic anhydride, oleic acid and diethyl benzenephosphonate, the quantity of said phosphonate being from 0.5 percent to 5.0 percent by weight of the weight of the maleic anhydride.

13. The process of preparing adducts which comprises heating at temperatures of from 150 C. to 300 C. a mixture comprising maleic anhydride, oleic acid and diphenyl 2-ethylhexanephosphonate, the quantity of said phosphonate being from 0.5 percent to 5.0 percent by weight of the weight of the maleic anhydride.

J OACHIM DAZZI.

REFERENCES CITED UNITED STATES PATENTS Name Date Rust Dec. 22, 1942 Number 

1. THE PROCESS OF PREPARING ADDUCTS WHICH COMPRISES HEATING AT TEMPERATURES OF FROM 150* C. TO 300* C. A MIXTURE COMPRISING MALEIC ANHYDRIDE, A FATTY ACID COMPOUND HAVING THE GENERAL FORMULA YCOOZ WHEREIN Y IS A NON-CONJUGATED OLEFINIC, ALIPHATIC HYDROCARBON RESIDUE OF FROM 9 TO 23 CARBON ATOMS AND Z IS A MEMBER OF THE GROUP CONSISTING OF HYDROGEN AND ALKYL RADICALS OF FROM 1 TO 8 CARBON ATOMS, AND A PHOSPHOROUS COMPOUND HAVING THE GENERAL FORMULA: 